JPH08154352A - Small size motor - Google Patents

Abstract

PURPOSE: To provide a small size motor in which drive coils are formed in small sizes with high precision and which can obtain a sufficient motor torque. CONSTITUTION: A small size motor 10 has a stator board 16 which is fixed and has drive coils 17 at least on one of its surfaces and a disc rotor 14 which is supported to rotate freely and to face the stator board 16 and is so magnetized as to have a plurality of poles. In the small size motor like this, the drive coils 17 are composed of a plurality of pattern layers formed on one of the surfaces of the stator board by a photolithography method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small motor having a stator substrate, a disc-shaped rotor, and a drive coil arranged on the stator substrate.

[0002]

2. Description of the Related Art Conventionally, such a small motor is constructed as shown in FIG. That is, FIG.
6, a small motor 1 includes a flat stator 2 and bearings 3 a and 3 b provided near the center of the stator 2.
And a rotary shaft 4 rotatably supported by the bearings 3a and 3b, and a rotor 5 fixed to the rotary shaft 4.

The bearing 3a is made of oil-impregnated metal or a lubricating resin so as to support the rotary shaft 4 in the radial direction, and the bearing 3b is thrust so as to support the rotary shaft in the axial direction. It is configured as a bearing.

The rotor 5 is arranged so as to face one surface (the upper surface in the case of the drawing) of the stator 2 and has an annular rotor magnet 5a attached to the lower surface thereof.

Here, the rotor magnet 5a is magnetized in multiple poles so that N poles and S poles are alternately arranged along the circumferential direction.

On the other hand, the stator 2 has a base 2a.
It is provided with a stator substrate 2b placed on top. This stator substrate 2b acts as a fixed yoke,
For example, while being formed of iron plate, electromagnetic steel plate, etc.,
To face each magnetic pole of this rotor magnet 5a,
It has a plurality of drive coils 6 arranged at equal angular intervals along the circumferential direction, and circuit elements such as Hall elements, resistors, capacitors, etc., which are not shown.

According to the small-sized motor 1 thus constructed, the magnetic field generated in the driving coil 6 by applying the current to each of the driving coils 6 on the stator substrate 2b is generated by the rotor magnet 5a. It acts on each north and south pole. As a result, the rotor 5 is rotationally driven around the rotation shaft 4.

[0008]

By the way, in recent years, downsizing and downsizing have been promoted in all the product fields, and there is a demand for downsizing and thinning of small motors used as drive sources for various devices. Is getting stronger.

Therefore, in the compact motor 1 as described above, in order to miniaturize it, it is necessary to particularly thin the driving coil 6. Therefore, in order to manufacture a thin drive coil, it is conceivable to use a product such as a flexible printed coil in which a coil is integrally formed on a resin base.

However, when the flexible printed coil is made thinner, it is necessary to form the driving coils with conductive patterns on both sides of the resin base. However, when the driving coils are formed on both sides, It is necessary to invert the resin base during manufacturing. Therefore, there is a problem that it becomes difficult to position the driving coil on both surfaces of the resin base.

On the other hand, when the drive coil is formed on only one surface of the resin base, the number of turns of the drive coil is reduced due to the width of the conductive pattern, and the motor torque is reduced. . Further, if the conductive pattern is miniaturized, the electric resistance of the conductive pattern increases, the current flowing through the drive coil decreases, and the motor torque decreases.

In view of the above points, the present invention has an object to provide a small motor in which a driving coil is formed in a small size with high accuracy and a sufficient motor torque can be obtained.

[0013]

According to the present invention, the above object is to provide a stator substrate fixedly arranged and provided with a drive coil on at least one surface thereof, and rotatable relative to the stator substrate. And a disk-shaped rotor provided with a magnet that is magnetized in multiple poles, and the driving coil is formed on one surface of the stator substrate by a photolithography method. This is achieved by a small motor characterized in that it is formed by a pattern of multiple layers.

The miniature motor according to the invention is preferably
The patterns of the plurality of layers are connected to each other as one group.

The miniature motor according to the invention is preferably
The above multi-layer pattern is divided into a plurality of groups,
The patterns of each group are connected to each other.

The miniature motor according to the invention is preferably
Of the plurality of groups of patterns, one group of patterns is used for position detection and / or speed detection.

The miniature motor according to the invention is preferably
A yoke layer for forming a magnetic path is formed on the stator substrate.

The miniature motor according to the invention is preferably
The pattern formed on the stator substrate is made of a magnetic material.

[0019]

According to the above structure, the driving coil is formed on one surface of the stator substrate by a pattern of a plurality of layers formed by the photolithography method, so that it is much thinner than the flexible printed coil. At the same time, extremely high dimensional accuracy and positioning accuracy can be obtained for the pattern forming the drive coil.

When the patterns of the plurality of layers are connected to each other as one group, the width of each pattern can be increased and the coil resistance value can be increased when the number of turns of the driving coil is the same. Is reduced. Therefore,
More drive current can be passed through the drive coil.

When the above-mentioned patterns of a plurality of layers are divided into a plurality of groups and the patterns of each group are connected to each other, a plurality of sets of driving coils which can greatly reduce the resistance value can be constructed. It will be possible.

When one group pattern among the plurality of group patterns is used for position detection and / or speed detection, an induced voltage is generated in this group pattern as the rotor rotates. Therefore, the induced voltage is detected and appropriately processed to detect the position and / or the rotation speed of the rotor.

When the yoke layer for forming the magnetic path is formed on the stator substrate, the magnetic flux of the rotor magnet passes through this yoke layer, and the interlinkage magnetic flux with the drive coil is generated. Increase. Therefore, the magnetic flux of the rotor magnet can be used more effectively.

When the pattern formed on the stator substrate is made of a magnetic material, since the drive coil is a magnetic material, the magnetic flux of the rotor magnet can be collected in this pattern. The generated torque increases.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to FIGS. In addition, since the Examples described below are preferred specific examples of the present invention, various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. The embodiment is not limited to these embodiments unless otherwise stated.

1 and 2 show a first embodiment of a small motor according to the present invention. That is, FIG. 1 and FIG.
In, the small motor 10 includes a flat stator 11 and
Bearing portion 11a formed near the center of the stator 11
It is composed of a bearing 12 provided in the lower part of the shaft, a rotating shaft 13 rotatably supported by the bearing portion 11a and the bearing 12, and a rotor 14 fixed to the rotating shaft 13.

The bearing portion 11a is adapted to support the rotating shaft 13 in the radial direction, and the bearing 12 is constructed as a thrust bearing so as to support the rotating shaft in the axial direction.

The rotor 14 is arranged so as to face one surface (the upper surface in the case shown) of the stator 11 and has an annular rotor magnet 14a provided on the lower surface thereof. This rotor magnet 14a is
In the case shown in the figure, it is formed as a separate body and is fixed to the lower surface of the rotor 14, but it may be formed directly on the lower surface of the rotor 14 by, for example, a sputtering method or the like. Further, the rotor 14 may be formed integrally with the rotating shaft 13.

Here, the rotor magnet 14a is magnetized in multiple poles so that N poles and S poles are alternately arranged along the circumferential direction.

On the other hand, the stator 11 has the base 1
5 is provided with a stator substrate 16 mounted thereon. As shown in FIG. 3, for example, the stator substrate 16 has a drive coil 17 formed on its surface by photolithography.
And electrodes 18 and the like are formed. Here, in this stator 11, the base 15 is preferably formed of a magnetic material or the stator substrate 16 in order to increase the magnetic flux interlinking with the driving coil 17 so as to effectively utilize the magnetic force of the rotor magnet 14a. Since the whole of the above or the region facing the rotor magnet 14a is made of a magnetic material, it acts as a magnetic path forming yoke.

Referring to FIG. 3, the steps of forming the driving coil 17, the electrode 18 and the like on the stator substrate 16 will be sequentially described. First, in step 1, the first insulating layer 20 is formed on the surface of the stator substrate 16. In this case, the insulating layer 2
The formation of 0 is performed by using PVD (Physical Vapor Depos) by using, for example, SiO ₂ or Si ₃ N _4.
method), CVD (Chemical Vapo)
r Deposition) method or the like, or by resin coating. When the stator substrate 16 is an insulator such as an Si substrate as an oxide of a material, the insulating layer 20 is formed by heating the stator substrate 16 to a high temperature in an oxidizing atmosphere.

Then, in step 2, the first conductive layer 21 to be a driving coil and a connection pattern is formed on the insulating layer 20. In this case, the conductive layer 21 is made of, for example, a conductor such as copper, aluminum, gold, nickel, PV
It is formed by the D method or plating.

Next, in step 3, the first conductive layer 21
A photoresist 22 which is a polymer resin material is applied from above and exposed in step 4 using the first photomask 30 shown in FIG. In this case, the first photomask 30 is configured to have windows 30a, 30b, and 30c in a part of the driving coil 17, the connection pattern, and the electrode 18, respectively, as illustrated. .

Then, in step 5, the excess unexposed photoresist 22 is removed by washing or the like, and in step 6, the portion of the first conductive layer 21 exposed by the removal of the photoresist 22 is removed by etching. It Then, in step 7, the residual photoresist 22 is removed using a solvent or the like that does not act on the first insulating layer 20 and the first conductive layer 21. Thus, a part of the driving coil 17 having a predetermined pattern, the connection pattern, and the first conductive pattern 23 to form the electrode 18 are formed.

Then, in step 8, a second insulating layer 24 is formed on the entire surface of the stator substrate 16 so as to cover the first conductive pattern 23.

Then, in step 9, the second insulating layer 24 is formed by using the second photomask 31 shown in FIG.
On the other hand, the energization window portion 24a is formed. in this case,
As shown in FIG. 5, the second photomask 31 is configured such that it has windows 31a and 31b at the connection terminal portion of each drive coil of the first conductive pattern 23 and the portion of the electrode 18, respectively. ing.

Next, in step 10, the third photomask 32 shown in FIG. 6 is used, and the procedure similar to steps 2 to 7 described above is followed. Conductive pattern 25 is formed. in this case,
As shown in the drawing, the third photomask 32 is configured to have windows 32a, 32b, and 32c in a part of the driving coil 17, the connection pattern, and the electrode 18, respectively.

Then, in step 11, the pattern is formed on the second conductive pattern 25 so as to cover the entire surface of the stator substrate 16 in order to prevent pattern short-circuiting due to adhesion of conductive dust and oxidation of the conductive layer. A third protective insulating layer 26 is formed.

Finally, in step 12, the power supply window portion 26a is formed in the third insulating layer 26 by using the fourth photomask 33 shown in FIG. In this case, the fourth photomask 33 is configured so as to have the window portion 33a in the portion of the electrodes 18 of the first and second conductive patterns 23 and 25.

Thus, the driving coil 1 composed of the first conductive pattern 23 and the second conductive pattern 25.
In FIG. 7, a plurality of coil patterns of the first conductive pattern 23 and the second conductive pattern 25 that are vertically overlapped with each other, and six coils in the illustrated case, are connected to each other as shown in FIG. As a result, the driving coils located on the opposite sides in the radial direction are connected in series, and
Of the three-phase drive coils of U-phase, V-phase, and W-phase connected in series, the other side of one drive coil is connected to each other, and the other side of the other drive coil is
Each of them is connected to one of the electrodes 18, and a three-phase driving coil 17 is formed.

The small motor 10 according to the present embodiment is configured as described above, and as shown in FIGS. 1 and 2, the electrode 1 is provided for each drive coil 17 on the stator substrate 16.
The magnetic field generated in the driving coil 17 by energizing each of them from the No. 8 is applied to each N of the rotor magnet 14a.
It acts on the pole and the south pole. As a result, the rotor 14
Is driven to rotate around the rotation axis 13.

According to this embodiment, the driving coil 17 is
Since the patterns 23 and 25 of a plurality of layers are sequentially formed on the one surface of the stator substrate 16 by the photolithography method, the pattern is very thin as compared with the flexible printed coil, and the driving coil 17 is provided. With regard to the pattern forming the above, extremely high dimensional accuracy and positioning accuracy can be obtained. Therefore, the characteristic deterioration of the motor caused by the decrease in the precision during manufacturing is extremely reduced. Further, since the patterns 23 and 25 are formed of a conductor layer of copper, aluminum, gold, nickel or the like, they are minute and have low resistance.

Therefore, for example, when the number of turns of the drive coil 17 is the same, as compared with the conventional one in which the drive coil is planarly formed by the conductive pattern on the stator substrate,
According to this embodiment, since the driving coil 17 is formed by the plurality of layers of patterns 23 and 25, the individual patterns 2
The width of 3, 25 can be widened, and the coil resistance value can be reduced. Therefore, a larger amount of drive current can be passed through the drive coil, which increases the generated torque.

When the coil resistance values are the same, the number of coil turns can be increased,
Similarly, the generated torque will increase. Further, the drive coil 17 does not need to be bonded or soldered for electrical connection as in the conventional case. Further, as in the case of manufacturing a semiconductor element, a large number of patterns of driving coils are formed at once on the base of a large stator, and the individual stator substrates are later cut, which enables mass production. Therefore, the work efficiency is increased and the cost is reduced.

By the way, in the above embodiment, the drive coil 17 is a group A composed of the first conductive pattern 23 and the second conductive pattern 25 formed on the stator substrate 16 by the photolithography method. It is composed of a coil. Then, as shown in FIG. 9, after forming the coils of the first group A on the stator substrate 16, by repeating steps 2 to 12 of FIG.
A second group B coil is formed on the first group A coil. In this case, each coil of the second group B is also connected to each other and to the electrode 18 similarly to the first group A shown in FIG. 8, so that the first group A and the second group B are connected. Will be connected as shown in FIG. 10 as a whole.

Here, the coils of each phase, that is, the U-phase, V-phase, and W-phase coils are respectively connected in series to each other as shown in the equivalent circuit of FIG. The two coils will be further connected in parallel. As a result, the coil in each phase has a resistance value that is half that of the case shown in FIG. Therefore,
According to the driving coil including the stacked first group A and second group B coils, the coil resistance value can be pushed low even if the width of the pattern is narrowed and the number of turns is increased. Therefore, a large torque can be obtained.

When the coils of the first group A and the second group B laminated as described above are provided, only the first group A is applied to the electrode 18 as in the case of FIG. Connected to each other and used as a drive coil,
The second group B is connected to an electrode different from the electrode 18, and this other electrode is used as a detection electrode.
The induced voltage generated in the second group B in association with the rotation may be detected. In this case, the rotation position and / or the rotation speed of the rotor 14 are detected by detecting the voltage generated in the second group B.

Further, since the pattern of the second group B is fine, the rotational position of the rotor 14 can be detected and / or
Alternatively, the rotation speed is detected with higher accuracy. Moreover,
Since the pattern of the second group B is arranged so as to correspond to the entire circumference of the rotor 14, it is possible to detect full time.

FIG. 12 shows a second embodiment of the small motor according to the present invention. That is, in FIG. 12, the small motor 40 is rotatable by the flat stator 41, the bearing 42 provided below the bearing portion 41 a formed near the center of the stator 41, and the bearing portion 41 a and the bearing 42. The rotation shaft 43 supported by the
And a rotor 44 fixed to.

The bearing portion 41a is adapted to support the rotary shaft 43 in the radial direction, and the bearing 42 is constructed as a thrust bearing so as to support the rotary shaft in the axial direction.

The rotor 44 is arranged so as to face one surface (the upper surface in the case shown) of the stator 41, and has an annular rotor magnet 44a provided on the lower surface thereof. This rotor magnet 44a is
In the case shown in the figure, it is formed separately and fixed to the lower surface of the rotor 44, but it may be formed directly on the lower surface of the rotor 44 by, for example, a sputtering method or the like. Further, the rotor 44 may be formed integrally with the rotating shaft 43.

Here, the rotor magnet 44a is magnetized in multiple poles so that N poles and S poles are alternately arranged along the circumferential direction.

On the other hand, the stator 41 has the base 4
Stator yoke 46 made of magnetic material provided on
And a stator substrate 47 provided thereon. The stator board 47 is the same as the stator board 1 described above.
Similar to 6, the driving coil 48, electrodes (not shown), etc. are formed on the surface by photolithography, for example, as shown in FIG.

In this case, since the base 45 and the stator substrate 47 of the stator 41 are made of a non-magnetic material, it is necessary to effectively utilize the magnetic force of the rotor magnet 44a and increase the magnetic flux interlinking with the drive coil 47. There is.
Therefore, the stator yoke 46 made of a magnetic material is provided.

Instead of providing the above-mentioned stator yoke 46, the stator substrate 47 may be provided with a magnetic layer 49 under the first insulating layer 50 as shown in FIG.

Here, the stator substrate 4 in FIG.
The steps of forming the magnetic layer, the driving coil 48, the electrodes, etc. on the substrate 7 will be sequentially described with reference to FIG. First, in step 1, the magnetic layer 49 that acts as a back yoke is formed on the surface of the stator substrate 47. The magnetic layer 49 is formed by using a magnetic material such as nickel or soft ferrite as P
It is performed by the VD method or the like. Next, in step 2, the first insulating layer 50 is formed on the surface of the stator substrate 47. In this case, the insulating layer 50 is formed by, for example, SiO.
_It is carried out by PVD method, CVD method or the like, or by resin coating using ₂ or Si ₃ N ₄ .
When the stator substrate 47 is an insulator such as a Si substrate, which is an oxide, the insulating layer 50 can be formed by heating the stator substrate 47 to a high temperature in an oxidizing atmosphere.

Then, in step 3, a first conductive layer 51 to be a driving coil and a connection pattern is formed on the insulating layer 50. In this case, the conductive layer 51 is made of a conductive material such as copper, aluminum, gold, nickel,
It is formed by the VD method or plating.

Next, in step 4, the first conductive layer 51
A photoresist 52, which is a polymer resin material, is applied from above and exposed in step 5 using the first photomask 30 shown in FIG.

Then, in step 6, the unexposed extra photoresist 52 is removed by cleaning or the like, and in step 7, the portion of the first conductive layer 51 exposed by the removal of the photoresist 52 is removed by etching. It Then, in step 8, the residual photoresist 52 is removed using a solvent that does not act on the first insulating layer 50 and the first conductive layer 51. Thus, a part of the driving coil 48 having a predetermined pattern, the connection pattern, and the first conductive pattern 53 that should form the electrode are formed.

Then, in step 9, a second insulating layer 54 is formed on the entire surface of the stator substrate 47 so as to cover the first conductive pattern 53.

Then, in step 10, this second insulating layer 5 is formed using the second photomask 31 shown in FIG.
4, an energization window portion 54a is formed.

Next, in step 11, the third photomask 32 shown in FIG. 6 is used and the procedure similar to steps 3 to 8 described above is followed, from the top of the second insulating layer 54 to the second step. Conductive pattern 55 is formed.

Subsequently, in step 12, the pattern is formed on the second conductive pattern 55 so as to cover the entire surface of the stator substrate 47 in order to prevent pattern short-circuiting due to adhesion of conductive dust and oxidation of the conductive layer. A third protective insulating layer 56 is formed.

Finally, in step 13, using the fourth photomask 33 shown in FIG. 7, a power feeding window portion 56a is formed in the third insulating layer 56.

Thus, the driving coil 4 composed of the first conductive pattern 53 and the second conductive pattern 55.
8, a plurality of coil patterns of the first conductive pattern 53 and the second conductive pattern 55 which are vertically overlapped with each other, and six coils in the illustrated case, are connected to each other as shown in FIG. As a result, the driving coils located on the opposite sides in the radial direction are connected in series, and
Of the three-phase drive coils of U-phase, V-phase, and W-phase connected in series, the other side of one drive coil is connected to each other, and the other side of the other drive coil is
Each of them is connected to one of the electrodes 18, and a three-phase drive coil 47 is formed.

According to the small-sized motor 40 having such a structure, the magnetic field generated in the driving coil 47 is generated by energizing the driving coils 47 on the stator substrate 47 from the electrodes. For each north and south pole of. As a result, the rotor 4
4 drives to rotate around the rotation axis 43.

Further, the magnetic flux of the rotor magnet 44a is effectively utilized by the stator yoke 46 arranged under the stator substrate 47 or the magnetic layer 49 formed on the stator substrate 47 acting as a back yoke. Will be. In the case of the magnetic layer 49, since the gap between the back yoke and the rotary magnet 44a is narrower, the interlinkage magnetic flux with the coil of the rotor magnet 44a is further increased.

Also in this case, the first group A is formed on the stator substrate 47 in the same manner as the stator substrate shown in FIG.
After forming the coil of No. 2, by repeating steps 3 to 13 of FIG. 13, the coil of the second group B may be formed on the coil of the first group A as shown in FIG. .

As a result, the coils of the respective phases, that is, the U-phase, the V-phase, and the W-phase, are further connected in parallel with the two coils of the first group and the second group which are connected in series with each other. In this case, the coils in each phase are compared with the coils of the first group A alone,
It becomes half the resistance value. Further, for example, only the coil of the second group B is connected to an electrode different from the electrode to which the drive voltage is applied.
When detecting the induced voltage generated in the second group B due to the rotation of No. 4, the rotational position of the rotor 44 is detected and / or
Alternatively, the rotation speed is detected.

FIG. 15 shows a third embodiment of the small motor according to the present invention. That is, in FIG. 15, the small motor 60 includes a flat stator 61, bearings 62a and 62b provided near the center of the stator 61, and a rotating shaft 63 rotatably supported by the bearings 62a and 62b. The rotor 64 is fixed to the rotating shaft 63.

The bearing 62a supports the rotating shaft 63 in the radial direction, and the bearing 62b is formed as a thrust bearing so as to support the rotating shaft in the axial direction. The small motor 60 according to the present embodiment is different from the small motor 10 shown in FIGS. 1 and 2 only in that the bearing 62a is provided.

The rotor 64 is disposed so as to face one surface (the upper surface in the case shown) of the stator 61, and has an annular rotor magnet 64a provided on the lower surface thereof. This rotor magnet 64a is
In the case shown in the figure, it is configured as a separate body and is fixed to the lower surface of the rotor 64, but it may be formed directly on the lower surface of the rotor 64, for example, by a sputtering method or the like. Further, the rotor 64 may be formed integrally with the rotating shaft 63.

Here, the rotor magnet 64a is magnetized in multiple poles so that N poles and S poles are alternately arranged along the circumferential direction.

On the other hand, the stator 61 has the base 6
5 is provided with a stator substrate 66. As shown in FIG. 3, for example, the stator substrate 66 has a driving coil 67 on its surface by photolithography.
And electrodes (not shown) and the like are formed. Here, in the stator 61, the base 65 is preferably formed of a magnetic material or the stator substrate 66 in order to increase the magnetic flux interlinking with the drive coil 67 so as to effectively use the magnetic force of the rotor magnet 64a. Since the whole of the above or the area facing the rotor magnet 64a is formed of a magnetic material, it acts as a magnetic path forming yoke.

According to the small motor 60 having such a structure, the magnetic field generated in the driving coil 67 is generated by energizing the driving coils 67 on the stator substrate 66 from the electrodes. For each north and south pole of. As a result, the rotor 6
4 drives to rotate around the rotation axis 63.

Here, since the drive coil 67 on the stator substrate 66 is formed by the photolithography method, the dimensional accuracy and the positioning accuracy of the coil winding are extremely high, and therefore, the accuracy is reduced during manufacturing. Motor characteristic deterioration is extremely reduced. Further, since the mutual connection of the drive coil 67 and the connection to the electrode are formed at the same time as the drive coil 67 by the photolithography method, the work of adhering the drive coil 67 onto the stator substrate 66 and the coil winding are performed. Since the soldering work for the electrodes of the terminal is unnecessary, the work efficiency is improved and the assembly cost is significantly reduced.

In this case, since the drive coil 67 is composed of a two-layer pattern of the first conductive pattern 23 and the second conductive pattern 25, the pattern of the drive coil 67 is different from that of the conventional flexible printed coil. Formed wide. Therefore, since the coil resistance value is reduced, a large drive current can be passed. Therefore, sufficient torque can be obtained.

In the above embodiment, the driving coil is composed of one group of coils or two groups of laminated coils, but the present invention is not limited to this, and the driving coil is
Furthermore, the coils of the third and fourth groups may be laminated to form a plurality of groups of coils. As a result, when the coils of each group are connected in parallel with each other, the combined resistance value of the coils is further reduced.

Further, by connecting only one group of coils among the plurality of groups of coils to another electrode and detecting the induced voltage generated in the coils of the group, the rotational position of the rotor 64 can be detected and / or detected. Alternatively, the rotation speed may be detected.

[0080]

As described above, according to the present invention, there is provided a very excellent small motor in which the driving coil is formed in a small size with high accuracy and sufficient motor torque can be obtained. Will be.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view showing a first embodiment of a small motor according to the present invention.

2 is a schematic cross-sectional view of the small motor of FIG.

FIG. 3 is a process chart sequentially showing an example of a manufacturing process of a stator substrate in the small motor of FIG.

4 is a plan view showing a mask used in the first conductive layer forming step of FIG. 3. FIG.

FIG. 5 is a plan view showing a mask used in the process of forming the conductive holes in FIG.

6 is a plan view showing a mask used in the second conductive layer forming step of FIG. 3. FIG.

FIG. 7 is a plan view showing a mask used in the power supply electrode forming step of FIG.

8 is a circuit diagram showing an example of connection of drive coils in the small motor of FIG.

9 is a cross-sectional view showing another configuration example of the stator substrate in the small motor of FIG.

FIG. 10 is a circuit diagram showing an example of connection of drive coils in the stator substrate of FIG.

11 is an equivalent circuit diagram of a coil formed by connecting the wires in FIG.

FIG. 12 is a schematic sectional view showing a second embodiment of the small motor according to the present invention.

13A to 13C are process diagrams sequentially showing another example of the manufacturing process of the stator substrate in the small motor of FIG.

14 is a cross-sectional view showing still another example of the manufacturing process of the stator substrate in the small motor of FIG.

FIG. 15 is a schematic sectional view showing a third embodiment of the small motor according to the present invention.

FIG. 16 is a schematic sectional view showing an example of a conventional small motor.

[Brief description of reference numerals]

 10 Small Motor 11 Stator 11a Bearing Part 12 Bearing 13 Rotating Shaft 14 Rotor 14a Rotor Magnet 15 Base 16 Stator Substrate 17 Driving Coil 18 Electrode 20 Insulating Layer 21 First Conductive Layer 22 Photoresist 23 First Conductive Pattern 24 Second Insulating layer 25 Second conductive pattern 26 Third insulating layer 30, 31, 32, 33 Photomask 40 Small motor 41 Stator 41a Bearing part 42 Bearing 43 Rotating shaft 44 Rotor 44a Rotor magnet 45 Base 46 Stator yoke 47 Stator substrate 48 Drive coil 49 Magnetic layer 50 Insulating layer 51 First conductive layer 52 Photoresist 53 First conductive pattern 54 Second insulating layer 55 Second conductive pattern 56 Third insulating layer 60 Small motor 61 Stator 62a, 62b axis Part 63 rotary shaft 64 rotor 64a rotor magnet 65 base 66 stator substrate 67 driving coil

Claims (6)

[Claims] 1. A stator substrate which is fixedly arranged and has a driving coil provided on at least one surface thereof, and a magnet which is rotatably supported facing the stator substrate and is magnetized in multiple poles. And a disk-shaped rotor having a disc-shaped rotor, wherein the driving coil is formed by a pattern of a plurality of layers formed by photolithography on one surface of the stator substrate. , Small motors. 2. The miniature motor according to claim 1, wherein the patterns of the plurality of layers are connected to each other as one group. 3. The small motor according to claim 1, wherein the patterns of the plurality of layers are divided into a plurality of groups, and the patterns of each group are connected to each other. 4. The pattern of the plurality of groups,
The pattern of one group is used for position detection and / or speed detection.
Small motor described in. 5. The small motor according to claim 1, wherein a yoke layer for forming a magnetic path is formed on the stator substrate. 6. The small motor according to claim 1, wherein the pattern formed on the stator substrate is made of a magnetic material.